Pump.



'No. 677,776. v Patented July 2, mm. J. DEVANTERY.

PUMP.

(Application filed May 12, 1900.)

(No Model.)

UNITED STATES i PATENT OFFICE.

JOSEPH DEVANTERY, OF NEW YORK, N. Y., ASSIGNOR TO THE LOCOMOBILE COMPANY OF AMERICA, OF SAME PLACE.

PUMP.

SPECIFICATION formingpart of Letters Patent No. 677,776, dated July 2, 1901.

Application filed May 12, 1900- s fl l No. 16,457. (No model.)

To all whom it may concern.-

Be it known that I, J OSEPH DEVANTERY, of New York, (Brooklyn,) in the county of Kin gs and State of New York, have invented certain new and useful Improvements in Pumps, of

which the following is a specification.

This invention has for its object to increase the capacity or delivery of pumps for pumping liquids; and it consists in an air-cushion-- 1b ing pocket or chamber combined with acheckvalve and disposed in a novel manner hereinafter specified, whereby a body of air is retained to act as a cushion which efiects a quick closing of the valve. f

Of the accompanying drawings, Figure 1 represents a side elevation, partly in section, of a pump embodying my improvement. Fig. 2 represents a section on line 2 2 of Fig. l.

The same reference characters indicate the same parts in both the figures.

Referring to the drawings, 1 designates the pun1p-cy1inder, and 2 is the contained piston operated in a suitable manner, as by an oscillatory lever 3 or any other suitable operating- 5 check-valve 7 is here represented as having a stem 10, guided within a central bore or aperture in the stem of the outlet check-valve 9, and the outlet-valve, furthermore, is ad apt-.

ed to act as a stop for the inlet-valve. I do not, however, herein claim this guiding and stop construction.

Above or back of the valve-seat Sis a chamber 11, which connects with and forms a part of the outlet or delivery branch 5. Beyond 5 said chamber 11 is a threaded opening formed in the pump-casing, into which is screwed a casing 12, the interior space 13 of which constitutes a closed air pocket or chamber. The mouth of said chamber is formed as a guide 14, which closely fits and guides the stem 15 of outlet check-valve 9. One or more small ports or ducts 1'6, bored through the inner end of the casing 12, form contracted passages connecting the air pocket or chamber 13 with the delivery-chamber 11, and hence with the 1 interior of the pump-cylinder 1.

' The operation of the above-described structure is as follows: The water or other liquid handled by the pump may be supposed to be accompanied by a greater or less quantity of air. It is well known that water under ordi nary conditions always contains a certain quantity of air in' a'diss olved or entrained condition. It may furthermore happen that at the beginping of pumping operations a certain amount of air will be passed through the pump along with or prior to the passage of the water. This air or a portion thereof will either be compressed out of the water into the air pocket or chamber 13 or when present in any quantity will find its way into said pocket through the ducts or passages 16 during the operation of pumping, this being par-- ticularly the case when the air-pocket 13 is uppermost, the tendency of the air being to rise. It is to 'be noted that the Valve-stem 15 projects within the air pocket or chamber 13, and when the check-valve 9 is unseated, due to the overflow of the contents of cylin-' der 1 when the piston 2 is driven inwardly, said stem will act as a piston entering the chamber and reducing the size of the space therein. The air in the pocket or chamber is thereby compressed and acts as a cushion, which immediately the inward stroke of the piston ceases reacts on the valve-stem 15 and returns the outlet check-valve 9 to its seat. The air, owing to its great elasticity, acts much more quickly than any spring could act, and by quickly seating the valve it prevents 0 the return of any of the liquid. The capacity or delivery of the pump is thereby increased over what it would be with a spring-closed or liquid-pressure-closedcheck-valve. During the movements of the valve the pumped liq- 5 uid in the chamber 11, covering the lower ends of ducts 16 and possibly extending'part way into chamber 13, will prevent the'escape of air from said' chamber. A similar cushioning action is exerted on the-inlet-valve 7 by virtue of the air chamber or pocket 17, which exists within the hollow valve-stem 15 above inlet-valve stem 10. To provide a duct or passage for the collection of the air within said pocket 17, the side of stem 10 may be slightly flattened or grooved longitudinally, as shown at 18, whereby a contracted passage to the cylinder-space is formed.

I claimn 1. In a pump, the combination of a cylinder and contained piston, a port or passage connected with the interior of the cylinder, a freely-movable check-valve controlling said port,and a closed air-pocket or chamber located behind the valve and connecting through a contracted passage with the interior of the pump-cylinder, said pocket being ada'pted'to retain a small body of air, which acts as a cushion to seat the valve,- said contracted passage being located in position to be sealed by the liquid being acted upon by the pump.

2. In a pump, the combination of a cylinder and contained piston, a port or passage connected with the interior of the cylinder, a freely-movable check-valve controlling said port,'and a closed air pocket or chamberlocated behind the valve and connecting through a contracted passage with the interior of the pump-cylinder, said pocket being adapted to retain a small body of air, which acts as a cushion to seat the valve, and having a valvestem guide at its mouth, the valve having a stem which projects through said guide into the pocket and operates as a piston therein, said contracted passage being located in position to be sealed by the liquid being acted upon by the pump.

3.. In a pump forliquids, the combination of a cylinder and contained piston, a port or passage connected with the interior of the cylinder, a freely-movable check-valve controlling said port and having a stem, a guide closely fitting said stem except at one or more points where relatively small air-passages are formed alongside of the stem, the said airpas'sages being located in position to be sealed by the liquid being acted upon by the pump, and a closed air chamber or pocket of substantial size, located behind the stem and connecting with the interior of the cylinder through said air passage-or passages, said pocket being adapted toretain a small body of air which acts as a cushion to seat the valve, and is retained in the pocket by the pumped liquid sealing said air passage or passages.

In testimony whereof Ihave affixed my signature in presence of two witnesses.

JOSEPH DEVANTERY.

Witnesses:

V. E. SGHAU'MB'URG, R. M. PIERSON. 

